1. Field of the Invention
The invention relates to an apparatus and a method for fabricating airlaid articles, and more particularly to a highly integrated apparatus for forming and dressing multidimensional fibrous pads such as sanitary napkins, diapers and the like.
2. Description of the Related Art
Several methods and devices for making sanitary napkins, diapers, and the like have been disclosed over the years, as reflected in the vast number of U.S. patents, some of which are listed below.
Most sanitary napkins utilize absorbent fibrous pads. The fibrous pad is obtained through the deposition of fluff on a drum-type air laying apparatus as shown in U.S. Pat. Nos. 1,950,765 and 2,073,329 to Winter in 1937 and in a great many patents issued in the following years. A more recent application of that basic principle is disclosed in U.S. Pat. Nos. 4,666,647 to Enloe et al and 4,592,708 to Feist et al.
Several fluff depositing, belt-type air laying apparatus are known as exemplified in U.S. Pat. Nos. 3,846,871 to Kolbach, 3,851,356 to Savich in 1974, 4,264,289 to Day, 4,375,447 to Chung, and many more.
From 1937 until the present both types of apparatus have been limited solely to obtaining a fibrous pad which is then transferred onto a conveyor where the dressing of the fluff, the sealing of the bottom and top material layers, and the cutting into the desired shape follow. Thus a finished product will appear at the end of an assembly line which includes several units and several conveyors.
Prior art patents disclose devices for manufacturing sanitary napkins and the like which do not possess the capability of creating a finished product directly on the anvil drum itself. Prior art teachings call for the cutting of the product into a given shape on an assembly line where the product continuously shifts left and right and thus the product cannot be cut evenly. Also, several transfers from the drum to the line and between different lines introduce inaccuracies and slow down the prior art devices quite substantially.
Finally, the prior art fluff preparing devices or pulp mills had certain shortcomings. It has always been necessary to use high-grade, and thus very expensive, pulp if good fluff was required. Good fluff, i.e. in which only few and very small chunks or knots of dry pulp are present in the fluff, is paramount in the manufacture of high quality sanitary napkins. Accordingly, only expensive dry pulp could previously be used in the manufacture of first grade napkins.